error: no such device: ad4103fa-...
Loading Linux core repo kernel...
error: file `/boot/vmlinuz-linux` not found
Loading initial ramdisk ...
error: you need to load the kernel first.

mount /dev/sda1 /mnt #sda1 is `boot` partition
mount /dev/sda3 /mnt/home #sda3 is `home` partition
arch-chroot /mnt
pacman -S os-prober
grub-install /dev/sda
grub-mkconfig -o /boot/grub/grub.cfg
exit
reboot